It's not. It's hilarious.

This movie is absulutely hilarious! It's fun for family, and haves a great lesson! Peter is super upset that Grandpa takes over his room, and he lives in the creepy attic. So Peter hatches a plan to play pranks like his shaving cream is a super hardening cream, and then Grandpa retaliates by writing something super bad and embarassing for Peter's summer paper. Then they also go to a trampoline park, and it's completly hilar! On and on pranks, cruel and funny, until it's Peter's sister's birthday party. And since she's addicted to christmas, it's a christmas themed! Peter thinks that his Grandpa is Santa, and plays a prank, but it wasn't his Grandpa! Everything starts to crumble, and they've ruined her party. They decide it isn't that bad, and settle. A great movie!